The present disclosure relates to a power tool which has an adjustable cutting depth, and more particularly, relates to a quickly adjustable cutting depth adjustment mechanism for the power tool.
A router generally comprises a base and a cutting unit which has a cutting bit mounted thereon. The cutting unit is movable relative to the base. In order to adjust the height of the bit relative to the workpiece, a depth adjustment mechanism is arranged between the base and the cutting unit.
By way of example, U.S. Pat. No. 5,853,274 discloses a router which comprises: (A) a base assembly which includes an annular base member and a cylindrical base member supported on the annular base member; (B) a cylindrical housing received within the cylindrical base member, wherein the cylindrical housing includes a plurality of vertically aligned first components; and (C) an adjustment mechanism supported on the base assembly, wherein the adjustment mechanism includes a lever and an adjustment device for moving the lever vertically with respect to the base assembly, and the lever has a second component which is movable between a first position and a second position. When at the first position, the second component is selectively engaged with one of the first components to prevent vertical sliding of the housing relative to the lever; when at the second position, the second component is disengaged with the first component so as to permit vertical sliding of the housing relative to the lever.
The adjustment mechanism disclosed hereinabove has several disadvantages. Firstly, the thickness of the first components is limited by the radial size of the cylindrical housing, so the distance between the first position and the second position is short, and thereby misoperation may happen. Secondly, the quick adjustment mechanism and the fine adjustment means move about the same axis, so interference may occur therebetween.